Rafael Nadal's feats on clay now are turning into his feet of clay.

Nadal's 30-match wininng streak on clay came to an end Friday when he lost to David Ferrer 7-6 (1). 6-4 in the quarterfinals of the Monte Carlo Rolex Masters, an event Nadal has won eight times and had 50-2 match record there coming into the match.

According to The Times of India, Nadal admitted his self-confidence took a hit during his semfinal loss to Stanislas Wawrinka at the Australian Open and has struggled so far this year to reclaim it.

"I don't have to lie to anybody," Nadal told reporters after the match, the Times of India reported. "After what happened in Australia it was little bit harder for me to find again the intensity, the confidence, the inside power that I always have."

Despite his self-doubt, Nadal won the Rio Open, a clay event, in February. But he lost in the third round of the BNP Paribas Open at Indian Wells in March and then lost to Novak Djokovic in the finals of the Sony Open in Miami at the end of last month.

Nadal, who sustained a back injury at the Australian Open, said he doesn't have any physical ailment for his current level of tennis.

"No, the back is in good shape. The physical performance is fine. No problem about that," he said. "Even if I won Rio, I played the final in Miami, it remains something in my mind and in my game," said Nadal.

"I'm going to fight to try to find that solution soon."

ESPN, however, reported that Nadal didn't sound as concerned with the loss in his post-match interview.

"I cannot be frustrated to lose a tennis match," Nadal told reporters after the match. "In the life, there is much more important things than a tennis match. But I am not happy with it. I feel that I have to do more than what I did today. So when you feel that you can do more, always you come back home or to the next tournament with not the best feeling. That's my feeling today.

"Yesterday, too, I played good, with confidence," he said. "But is not that problem. "The problem is when the match became little bit more to the limit, and not answering the right way as I normally do. So that's it."

The next big test of confidence for Nadal comes at the French Open next month at Roland Garros.

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